If statement with conditional formatting - "containing a value"

I have put in conditional formatting on my seating plan I am setting up, that compares the students current grade with their target grade.

If the current grade is higher than the target - the cell turns green.

=IF(G4>G5,TRUE, FALSE) If the current grade is lower - the cell turns red.

=IF(G4 =IF(G4=G5,TRUE, FALSE)

The problem occurs when the current grade contains a - or a + after the grade. e.g Target = C Current = C+

I want to change the formula in the conditional formatting for this so that if it CONTAINS the grade in the 3 levels cell then if turns orange.

Any ideas??

Thanks